I have macOSSierra 10.12.5, I have checked the keyboard shortcuts in system preferences and Cmd ⌘ ` (command + backtick) is enabled indeed!
Yet, when I open two finder windows (not the tabs), I cannot cycle between them. I explicitly have to right click on the finder icon in the doc and select one of the open folders. This is bad, really bad for productivity, since I have to switch every time between mouse and keyboard.
Is there a way out of this ?